What is the “best route” to connect multiple sites?

I’m doing a project for school and I’m looking for prices to connect 5 different sites, but most of the pricing requires contacting a sales rep. I’m wondering if anyone can help with pricing for T1, T3 and cable.
We’ve got four satellite sites connecting to a main site through frame relay via EIGRP. At the main site we are thinking of using two connections and load-balancing the input.
What would be the monthly costs? Rough estimates are fine (kinda expected) and the “site” is in Tx.
Any help would be appreciated.
Thanks
Can post more details if needed.